Patent · US Expired

Centralizer for wireline tools

US7090007B2 · kind B2 · utility

23Cited by
20References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 20, 2001
Grant dateAug 15, 2006
Priority date
Expiry dateOct 31, 2021

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B17/1021
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A centralizer for use in oil well wireline toolstrings comprising a central mounting rod and floating spring mechanisms between which a number of jointed centralizer arms are connected. The jointed centralizer arms have a section with a concave profile disposed near to their pivot points so that a closing force acting on the arms acts at a greater distance from the pivot, thereby increasing the closing moment and making the centralizer easier to draw into a borehole with a narrow cross-section. The floating spring mechanisms also have a linkage to the presser plate of the spring such that an axial force pulling the centralizer apparatus into a borehole is transferred directly into a force on the spring, thereby reducing the opening moment the springs exert on the centralizer arms.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.